THE RECYCLE AND REUSE OF CAUSTIC WASTE STREAMS USING A NOVEL CRYSTALLIZATION TREATMENT PROCESS IN THE REFINING AND CHEMICAL INDUSTRIES

Sodium and potassium hydroxide are two of the most commonly encountered bases in the chemical and refining industries. Their application ranges from use as a reagent in the manufacture of various industrial and food products to the neutralization of acidic byproducts, wastewaters and gaseous streams stemming from these manufacturing operations. In many cases, the spent caustics are discharged to a wastewater treatment plant (WWTP) for treatment prior to surface water or POTW discharge. This necessitates the ongoing purchase of fresh caustic for the source operation along with the ongoing burden of having to treat the spent caustic. When the acidic byproducts contain tightly regulated and/or toxic constituents (such as fluoride), the WWTP is additionally taxed to meet increasingly tighter NPDES and/or POTW discharge criteria as effectively and economically as possible.